JPS5922760B2 - Release agent - Google Patents

Description

[Detailed description of the invention] The present invention relates to a mold release agent.

For details, see the manufacture of ceramic products, such as refractory bricks, tiles,
Forming of raw materials with a moisture content of 30% or less mainly composed of silica or alumina, such as ceramics, insulators, casting molds, and roof tiles, and manufacturing of concrete products, such as U
This invention relates to a mold release agent suitable for molding grooves, side gutters, piles, flat plates, etc.

When molding ceramic products and concrete processed products,
Raw materials are injected into a mold made of metal, wood, plywood, cardboard, plastic, etc., and after the raw materials have hardened, they are taken out of the mold and made into a product.

These types of molds have poor releasability with the product, so when the product is removed from the mold, part of the product adheres to the mold, causing unevenness and impairing the aesthetics, or vice versa. Fragments of the formwork may adhere to the surface of the product, causing damage to the formwork.

For this reason, a mold release agent is usually applied to the mold by spraying or brushing to perform mold release.

The following conditions are required for this mold release agent.

(1) Excellent mold release effect, (2) Good precision of the molded product, (3) Little wear on the mold frame, (4) Excellent workability, (5) Low cost. (6) Stable supply is possible and quality is constant;
(Power) There should be little negative impact on workers.

Conventionally, as a mold release agent, a mixture of vegetable oil such as rapeseed oil or rice bran oil or fish oil with kerosene or spindle oil has been used.

However, these conventional products had uneven mold release effects, and as a result, many molded products were defective.

On the other hand, there are many problems related to the working environment, such as the presence of odor and the tendency for workers' skin to become irritated.

The mold release agent of the present invention is a new composition that improves the drawbacks of these conventional products, and has an excellent mold release effect and an effect of preventing damage to molds.

The mold release agent of the present invention is effective for molding ceramic products and concrete processed products, and is particularly effective for molding using a metal mold as a formwork.

The present invention provides a mold release agent comprising 1 part by weight of an oily agent and 1 to 20 parts by weight of mineral oil, wherein the oily agent is (a), C1□-2o
One or more fatty acids selected from the group consisting of saturated fatty acids and C18-22 unsaturated fatty acids 50-96
% by weight, and (0), one or more fatty acids selected from the group consisting of C12-20 saturated fatty acids and C18-2□ unsaturated fatty acids, and one or two selected from C1-8 alcohols. One or two types of fatty acid esters synthesized from monohydric alcohols of 4 to 50 types
% by weight of a mold release agent.

In order to obtain an excellent mold release effect, the mold release agent applied to the mold must wet the metal surface evenly and uniformly, and must have an oil film strength sufficient to withstand external pressure.

The adsorption power of the oil-based agent is most closely related to the wetting of the metal surface and the strength of the oil film, but it is thought that animal and vegetable oils, which have traditionally been known as components of mold release agents, are physically adsorbed to the metal surface. Since the adsorption power is weak and it is difficult to wet, excellent mold release effects cannot be expected.

On the other hand, since the fatty acid, which is a component of the oily agent used in the present invention, has a polar group at its end, this polar group is chemically adsorbed onto the metal surface, and the alkyl group is oriented in the opposite direction, which reduces friction. There is.

That is, it is thought that these fatty acids are adsorbed onto the metal surface and form an oriented monomolecular solid film.

The strength of the adsorption force is determined by the adhesion energy, and the magnitude of this adhesion energy is represented by the heat of adsorption.

According to the experiments of A, J. and Gutsuri Sek (ASLEl-Ranzakjon Vol. 5, p. 105, 1962), heat of adsorption is associated with wear resistance. If an acid or cetylamine is used, an oil-based agent with a small amount of wear in a four-ball test can be obtained.

However, when these oil-based agents are actually used as mold release agents, although they have a superior mold release effect compared to conventional mold release agents, they cannot prevent sufficient buildup from mold wear. There wasn't.

The inventors of the present invention have discovered that a mold release agent having an extremely excellent mold release effect can be obtained by mixing a certain amount of fatty acid ester with this fatty acid, and have completed the present invention.

The excellent mold release effect in the present invention was obtained for the first time from a combination of fatty acids and fatty acid esters.

The synergistic effect of fatty acids and fatty acid esters will be clarified later in Examples, and the reason is thought to be as follows.

In other words, the area occupied by the oriented alkyl groups in the solid film of fatty acids is smaller than the area occupied by the polar groups adsorbed on the metal surface. It is thought that the combined use of fatty acid ester compensates for these dents, making the surface of the oil film smooth and strengthening the oil film.

Each component of the present invention will be specifically explained below.

The fatty acid that is one component of the oily agent is one or more fatty acids selected from the group consisting of C1□-2o saturated fatty acids and C18-22 unsaturated fatty acids.

If the number of carbon atoms in the fatty acid is smaller than this range, the alkyl group will not be oriented well at low temperatures, resulting in oil film breakage, which is undesirable.If the number of carbon atoms in the fatty acid is larger than this range, it will not be compatible with other components such as mineral oil. Due to decreased solubility,
It is also unfavorable from the standpoint of storage stability.

Preferred fatty acids in the present invention include C1□-2o saturated fatty acids such as lauric acid, myristic acid, stearic acid, and palmitic acid, and C18-22 unsaturated fatty acids such as oleic acid, linoleic acid, and lylunic acid. be.

In addition to these simple fatty acids, animal and plant fatty acids containing these simple fatty acids can also be used, and examples of the plant and animal fatty acids include soybean fatty acids, rapeseed fatty acids, and beef fatty acids.

The fatty acid ester, which is another component of the oily agent, is C12-
One or more fatty acids selected from the group consisting of C18-20 saturated fatty acids and C18-22 unsaturated fatty acids and 01
It is one type or a mixture of two or more types of fatty acid esters synthesized from one or more types of monohydric alcohols selected from -8 alcohols.

If the number of carbon atoms in the fatty acid in the fatty acid ester is smaller than this range, the alkyl group will not be oriented well at low temperatures, resulting in oil film breakage, which is undesirable, and if the number of carbon atoms is larger than this range, it will be difficult to mix with other components such as mineral oil. This is unfavorable from the viewpoint of storage stability, since the compatibility of

The fatty acid that induces the fatty acid ester in the present invention is C12
-20 saturated fatty acids or C18-2□ unsaturated fatty acids, examples of the former include lauric acid, myristic acid, stearic acid, palmitic acid, etc., and examples of the latter include oleic acid, linoleic acid, liluic acid, etc.

In addition to these simple fatty acids, animal and plant fatty acids containing the simple fatty acids can also be used, and the animal and plant fatty acids include soybean fatty acid,
Examples include rapeseed fatty acid and beef tallow fatty acid.

On the other hand, the alcohol is preferably a C1-8 monohydric alcohol, particularly a 1-4 monohydric alcohol, and specifically, methyl alcohol and butyl alcohol are most preferred.

Among fatty acid esters derived from these fatty acids and alcohols, beef tallow methyl ester, beef tallow butyl ester, stearic acid butyl ester, and castor oil ester are particularly preferred.

The oily agent used in the present invention contains 50 to 96% by weight of fatty acids,
Fatty acid ester 4-50% by weight, preferably fatty acid 60%
It is a mixture of ~94% by weight and 6-40% by weight of fatty acid ester.

In this case, if the amount of fatty acid ester is less than 4% by weight, no synergistic effect between the fatty acid and the fatty acid ester can be expected, and if the amount of fatty acid ester exceeds 50% by weight, the mold release effect will be reduced.

The mineral oil referred to in this invention has a viscosity of 2 at 37.8°C.
Lubricating oil fractions and kerosene with ~500 cSt can be used, and among the lubricating oil fractions, machine oil, spindle oil,
Particularly preferred is turbine oil.

These mineral oils can be used alone or in combination of two or more, and a particularly preferred method of use is in combination with an appropriate amount of machine oil or spindle oil to adjust the viscosity of the product mold release agent and an appropriate amount of kerosene for dilution. It is also economically superior.

The mixing ratio of the oily agent, which is a mixture of fatty acids and fatty acid esters, and mineral oil is 1 to 20 parts by weight of the oily agent.
Parts by weight are preferred.

Further, depending on the application, the mold release agent of the present invention can be used by further diluting the mold release agent having the above-mentioned mixing ratio with mineral oil such as kerosene.

For example, from the standpoint of storage, transportation, etc., it is preferable to prepare a mold release agent consisting of 1 part by weight of an oil-based agent and 1 to 3 parts by weight of mineral oil and dilute it with mineral oil before use.

This dilution ratio can be selected as an appropriate value depending on the purpose of use. For example, taking a mold release agent consisting of 1 part by weight of an oil-based agent and 1 part by weight of mineral oil, it is suitable for the production of firebrick (in this case, mold release agent). 0 to 3 parts by weight of mineral oil to 1 part by weight of agent, 1 to 4 parts by weight of mineral oil to 1 part by weight of mold release agent in the manufacture of tiles, and 1 to 4 parts by weight of mineral oil to 1 part by weight of mold release agent in the manufacture of insulators. 5
~12 parts by weight, 9 to 15 parts by weight of mineral oil per 1 part by weight of mold release agent in the manufacture of roof tiles, 0 to 3 parts by weight of mineral oil per 1 part by weight of mold release agent in the manufacture of ceramics, manufacturing of casting molds ( In this case, it is preferable to use a mixture of 5 to 8 parts by weight of mineral oil per 1 part by weight of the mold release agent.

If the amount of mineral oil is too large (this will cause the oily agent to be excessively diluted and the mold release effect will decrease).

Furthermore, if the amount of mineral oil is too small, the viscosity will be too high, reducing workability, and it is also economically unfavorable.

The mold release agent of the present invention is characterized in that it has an excellent mold release effect and mold damage prevention effect by using a mixture of fatty acids and fatty acid esters as an oily agent. It is possible to add extreme pressure agents.

For example, this is the case when manufacturing a cylindrical injection pipe using firebrick, or when manufacturing a U-shaped groove using concrete, and the pressure applied to make the interior hollow is 300 to 100 ml.
0 0 0 kg/ffl, which is extremely severe. Extreme pressure performance is therefore required.

In addition to animal sulfurized oil, metal-based and other types of extreme-pressure agents can be considered, but metal-based agents are not preferred because metals may migrate into the product.

Furthermore, sulfurized oils with too high a sulfur content are not preferred because they may cause yellow spots on the products during the production of roof tiles, insulators, ceramics, and the like.

As the sulfurized animal oil that can be used in the present invention, sulfides such as sulfurized whale oil, fish oil, and cod liver oil can be used, and among these, sulfurized whale oil is particularly preferred.

These animal sulfurized oils are contained in the mold release agent of the product in an amount of 0.02 to 0.40 parts by weight, particularly 0.06 to 0.40 parts by weight, per 1 part by weight of the oily agent.
It is preferable to add 20 parts by weight.

If the amount added is too small, the effect of the addition will be small, and if it is too large, it will have an unfavorable effect on the properties of the product.

The composition and effects of the mold release agent of the present invention will be specifically explained below using Examples and Comparative Examples.

Examples 1 to 8 and Comparative Examples 1 to 7 Various mold release agents as shown in the table were manufactured and tested on actual machines by molding firebricks, tiles, roof tiles, injection pipes, concrete U-shaped grooves, and the like.

For evaluation of the test, the following mold release degree rating was used.

Rating of mold release: O: The product broke after molding.

Mold release degree rating: 2: Mold release was performed using the mold release agent of Example 1, which was made by diluting machine oil with a viscosity of 30 cSt at 50°C three times with kerosene.

Rating of degree of mold release: 10; no damage to the product or mold was observed with the naked eye after molding.The properties of the various oil agents, extreme pressure agents, mineral oil and diluent used were as follows.

Rapeseed fatty acid (acid value 190, iodine value 120) Oleic acid (neutralization value 2001 iodine value 92) Stearic acid (neutralization value 198, iodine value 18) Soybean fatty acid (neutralization value 176, iodine value 120) Beef tallow methyl ester ( Saponification value 193, iodine value 58) Stearic acid butyl ester (saponification value 172, iodine value 0.9) Castor oil fatty acid methyl ester (saponification value 184, iodine value 87) Beef tallow butyl ester (saponification value 196, iodine value Value 61) Sulfurized whale oil (sulfur content 9% by weight) Machine oil (viscosity 42 cSt @ 5Q°C) Spindle oil (viscosity 14.5 cSt @ 30°C) Kerosene (JIS No. 1) Examples 1 to 6 are various fatty acids Mineral oil is added to an oil-based agent consisting of various fatty acid esters as a mold release agent, and this is diluted with kerosene.

The compositions of Examples 1 to 6, which used a mixture of fatty acids and fatty acid esters as oily agents, were different from the compositions of Comparative Examples 2 to 5 (
It has an excellent mold release effect compared to this ratio.

That is, Comparative Example 2 used naphthenic acid, Comparative Example 3 purified rapeseed oil, Comparative Example 4 used rapeseed fatty acid, and Comparative Example 5 used methyl beef tallow and purified rapeseed oil as oily agents. It was 2-8.

On the other hand, the mold release degree ratings of the compositions of Examples 1 to 6 were all lO
It has excellent performance as a mold release agent.

Further, by comparing the compositions of Examples 3 and 4 with the compositions of Comparative Examples 6 and 7, a preferred range of the mixing ratio of fatty acids and fatty acid esters will be explained.

The oily agent of Example 3 is a mixture of 89% by weight of rapeseed fatty acid and 11% by weight of beef tallow methyl ester, and the oily agent of Example 4 is a mixture of 79% by weight of rapeseed fatty acid and 21% by weight of beef tallow methylester, and both of them are The moldiness rating was lO.

On the other hand, the oily agent of Comparative Example 6 is a mixture of 96% by weight of rapeseed fatty acid and 4% by weight of beef tallow methyl ester, and the oily agent of Comparative Example 7 is a mixture of 45% by weight of rapeseed fatty acid and 55% of beef tallow methyl ester.
% by weight, and the mold release degree ratings were 8 and 8, respectively.

Therefore, as mentioned before, the mixing ratio of fatty acids and fatty acid esters is 50 to 96% by weight of fatty acids and 4% by weight of fatty acid esters.
Obviously, a range of 50% by weight is preferred.

Examples 7 and 8 are mold release agents made by adding animal sulfide oil as an extreme pressure agent to an oil-based agent consisting of fatty acids and fatty acid esters, and are useful not only for the molding of refractory bricks but also for injection pipes or concrete U-shaped grooves. Even under severe conditions such as molding, the mold release degree rating was 10.

Therefore, those to which animal sulfurized oil is added as an extreme pressure agent can also be said to be particularly preferable as the mold release agent of the present invention.

Claims (1)

[Claims] 1. A mold release agent consisting of 1 part by weight of an oily agent and 1 to 20 parts by weight of mineral oil, where the oily agent is (a) 1 selected from the group consisting of C1□-2° saturated fatty acids and C18-22 unsaturated fatty acids. Seeds or two or more fatty acids 50-960
96 parts by weight), C1□-2□ saturated fatty acids and C18
A fatty acid ester consisting of one or more fatty acids selected from the group consisting of -22 unsaturated fatty acids and one or more monohydric alcohols selected from the alcohols 01-8. A mold release agent characterized by containing 4 to 50% by weight of one species or two or more species.